Elastic wave propagation in a single-layered hexagonal boron nitride metamaterial

Abstract

Wave propagation in a single-layered hexagonal boron nitride ( h-BN) metamaterial is investigated by molecular dynamics (MD) simulation and the finite element method (FEM). The molecular model for a single-layered h-BN metamaterial is established. The transmission performance of elastic waves in metamaterials is simulated by the MD method. The MD simulation results show that the metamaterial has an elastic wave bandgap in the frequency range of THz. The edge states in the bandgap region are found by the MD method and FEM, and the wave propagation is confined to the boundary only. The results obtained by the FEM roughly agree with those of MD simulations. The difference in the bonding structures between the atoms at the boundary and interior of the metamaterial results in the differences between the FEM and MD results. The size effect on the bandgap structure is studied by comparing the transmission curves of the metamaterial with different unit cell sizes. The size effect becomes more substantial with decreasing feature size of the metamaterial. This work can be helpful for the vibration suppression of nanoelectromechanical systems.